The present invention relates to a contact element for an electrical plug connector.
In a known contact socket element of this type which can be manufactured by automatic means (West German Pat. No. 15 90 124), the bearing piece which bears the contact springs is comprised of a sleeve, and the contact springs extend at an angle to the axis of the sleeve and have bent-around ends which are attached to the edge of the sleeve. Since the contact springs have a configuration including an element corresponding to a set of generatrices of a hyperboloid of revolution, they have the minimum mutual transverse separation in approximately their middle region, considered in an axial cross section through the sleeve with the contact springs mounted on it. Accordingly, these are the locations of the contact loci where the contact pin or plug comes into electrically conducting contact with the contact springs.
It has proven to be disadvantageous with these known contact spring sockets that one must have a relatively large sleeve to mount the contact springs and hold them in place, in which sleeve only a few contact springs can be inserted, sequentially, followed by the relatively costly effort of attachment of their end faces. These problems are particularly acute in the case where one attempts miniaturization of contact spring sockets, having diameters less than 1 mm.
In a contact element in the form of a contact spring socket or spring-loaded pin or plug, according to an older unpublished West German Patent Application No. P 36 08 276.7, the contact springs are connected by metallic conducting means on one of their ends to form a mat-like contact spring unit, the springs running mutually perpendicularly, and are given a radially curved configuration, following which this unit is rolled into a cylindrical shape which enables attachment to a separate support piece. This eliminates the problem arising in the manufacture of previously known contact elements as seen in West German Pat. No. 25 58 003 wherein a mat-like contact spring unit has contact spring wire bent into a wave shape, wherein the contact spring wire segments, which run parallel to each other, are interconnected by arcuate conductor segments. Because in practice there is a minimum practicable radius of curvature for the curved connecting segments, there is in practice a minimum mutual separation distance of the contact spring wire segments. Further, it has been found difficult to manipulate the contact spring mat of the type described in West German Pat. No. 25 58 003 because of its inherent flexibility and its elasticity. In particular, distortion results from the fact that the arcuate segments resist bending around an axis parallel to the contact spring wire segments.
The underlying problem of the present invention is to devise a contact element of the type referred to initially supra, which element has a relatively simple structure, can be inexpensively manufactured, and is of compact size, preferably for use with plug connectors, yet has high current carrying capacity and low required plug insertion forces.